[vdr] Re: VDR Plugin System - First Step

[Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de>]

Stefan Huelswitt wrote:
> 
> On 09 May 2002 Klaus Schmidinger <Klaus.Schmidinger@cadsoft.de> wrote:
> 
> > I suggest that the authors of VDR patches try to implement the "command line",
> > "menu", "setup" and "i18n" parts of their patches, using the new plugin features, and
> > let me know which remaining functions they would still need to patch VDR
> > source files for. What I already am planning to implement are generalized
> 
> Just had a quick view at the documentation. Sounds goods. I
> haven't created any code until now, but I see something missing
> for me: you cannot insert a listobject in the middle of a list. I
> would suggest:
> 
> void cListObject::Insert(cListObject *Object)
> {
>   if(next) { // Allow inserting an object in the middle of the list
>     next->prev = Object;
>     Object->next = next;
>     }
>   Append(Object);
> }
> 
> void cListBase::Add(cListObject *Object, cListObject *AfterThis)
> {
>   if (lastObject) {
>      if(AfterThis) { AfterThis->Insert(Object); return; }
>      lastObject->Append(Object);
>      }
>   else
>      objects = Object;
>   lastObject = Object;
> }
> 
> with the declaration (for default behaviour):
> 
>   void Add(cListObject *Object, cListObject *AfterThis=NULL);
> 
> And for the MenuItem handling (to add an item below the current):
> 
> void cOsdMenu::Insert(cOsdItem *Item, bool Current)
> {
>   cList<cOsdItem>::Add(Item,Get(current));
>   if (Current)
>      current = Item->Index();
> }

I'm not sure if this is the right way to do this.

With your method you won't be able to insert an item before the very first item
of a list - and I guess a common solution should provide this capability.

So I'd suggest that cListObject::Insert(cListObject *Object) should insert
'Object' *before* the cListObject, and maybe it would be better to call that
function cListObject::Prepend(cListObject *Object) then (according to the other
function being called 'Append()').

Consequently cListBase::Add(cListObject *Object, cListObject *AfterThis) should
be accompanied by a new cListBase::Ins(cListObject *Object, cListObject *BeforeThis)
to allow full flexibility.

Finally, cOsdMenu::Add() should be the one offering to add *after* a given
item, and cOsdMenu::Ins() should insert *before* a given item.

Klaus
-- 
_______________________________________________________________

Klaus Schmidinger                       Phone: +49-8635-6989-10
CadSoft Computer GmbH                   Fax:   +49-8635-6989-40
Hofmark 2                               Email:   kls@cadsoft.de
D-84568 Pleiskirchen, Germany           URL:     www.cadsoft.de
_______________________________________________________________